# HG changeset patch
# User Mike Becker <universe@uap-core.de>
# Date 1707943412 -3600
# Node ID f4faa7f73cb8db2ec8cb9bf0733d1ed6d75b9d7b
# Parent  e2243453127fe109b6e42430eb649819438e34ba
declare cx_tree_search_func function pointer

diff -r e2243453127f -r f4faa7f73cb8 src/cx/tree.h
--- a/src/cx/tree.h	Wed Feb 14 21:31:38 2024 +0100
+++ b/src/cx/tree.h	Wed Feb 14 21:43:32 2024 +0100
@@ -87,6 +87,29 @@
         ptrdiff_t loc_next
 );
 
+/**
+ * Function pointer for a search function.
+ *
+ * A function of this kind shall check if the specified \p node
+ * contains the given \p data or if one of the children might contain
+ * the data.
+ *
+ * For example if a tree stores file path information, a node that is
+ * describing a parent directory of a filename that is searched, shall
+ * return 1 to indicate that a child node might contain the searched item.
+ * On the other hand, if the node denotes a path that is not a prefix of
+ * the searched filename, the function would return -1 to indicate that
+ * the search does not need to be continued in that branch.
+ *
+ * @param node the node that is currently investigated
+ * @param data the data that is searched for
+ *
+ * @return 0 if the node contains the data,
+ * 1 if one of the children might contain the data,
+ * -1 if neither the node, nor the children contains the data
+ */
+int (*cx_tree_search_func)(void const *node, void const* data);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif